Apparatus and method for applying helical wire wrapping



K. D. BROWN Feb. 7, 1967 APPARATUS AND METHOD FOR APPLYING HELICAL WIRE WRAPPING 2 Sheets-Sheet 1 Original Filed Aug. 5, 1959 FIG.

INVENTOR. K E N A RD 0. 3 R0 WN g3 ATTORNE YS K. D BROWN Feb. 7, 1967 APPARATUS AND METHOD FOR APPLYING HELICAL WIRE WRAPPING 2 Sheets-Sheet 2 Original Filed Aug. 5, 1959 INVENTOR.

KENARD 0. BROWN ATTORNEYS United States Patent 3,302,379 APPARATUS AND METHOD FOR APPLYING HELICAL WIRE WRAPPING Kenard D. Brown, 1227 S. Wiilow St, Casper, Wyo. 82601 Original application Aug. 3, 1959, Scr. No. 831,260, now Patent No. 3,174,512, dated Mar. 23, 1965. Divided and this application Mar. 18, 1965, Ser. No. 440,836

6 Claims. (Cl. 57--9) The present application is a division of my copending application Serial No. 831,260, filed August 3, 1959, which issued on March 23, 1965, as Patent No. 3,174,512 and includes subject matter also disclosed in my co pending application Serial No. 281,615, filed May 20, 1963, which is also a division of my aforesaid application, and now Patent No. 3,234,723.

The present invention relates to an improved apparatus and method for applying a helical wire wrapping to tubular structures and the like.

In the above identified applications I have disclosed a reinforced tubing comprising a liner of synthetic plastic or similar material reinforced by a helical wrapping of wire and having longitudinal tension wires secured over the helical wrapping and maintained in place by a helical wrapping of similar wire having its coils spaced substantially from one another. In the aforesaid applications the wires are provided with low friction protective coatings of synthetic plastic.

It is an object of the present invention to provide an improved method for wrapping helical coils of wire about plastic tubing and the like.

It is another object of the present invention to provide an improved method for wrapping tight helical coils of wire about plastic tubing and the like.

It is another object of this invention to provide an improved apparatus for effecting the continuous wrapping of helical coils about a tubular liner and the like and for placing the wire about the tubing in a tightly wound helix pattern.

Briefly, in carrying out the objects of this invention in one embodiment thereof, a coil winding machine is provided which may be employed in the practice of the method of the invention. The machine is similar in construction to a lathe and has a hollow central core through which is passed the tubing or other structure to be wrapped. A reel of the wire to be wrapped about the tubing is mounted on a winding attachment which rotates about the tubing as it passes through the hollow core. The wire is passed through a tensioning device and then about a preforming roller and thence passes to the tubing and is wrapped about the tubing by rotation of a coil winding support. By preforming the coil to a sufliciently small diameter it may be formed about the tubing in gripping engagement and, by adjusting the relative speed of the winding motor and the drive of a take-up reel, the helical wire is applied in closely wrapped or touching turns in intimate contact with the tubing.

The features of novelty which characterize this invention are pointed out with particularly in the claims annexed to and forming a part of this specification. The invention itself, however, both as to the procedure of the method and the construction of the apparatus, together with further objects and advantages thereof, will be better 3,362,319 Patented Feb. 7, 1967 understood upon reference to the accompanying drawings in which:

FIG. 1 illustrates the method and apparatus for applying tightly wound helical coils to a plastic liner; and

FIG. 2 is an elevation view of the apparatus of FIG. 1 showing further features of the apparatus and method.

Referring now to the drawings, in FIG. 1 a liner or tubing 12 has been shown in position for wrapping by a coiling machine embodying the invention. The tubing 12 may be the liner of a composite tubing such as that disclosed in the above entitled parent application and is wrapped with a wire 16 which may be a high tensile strength wire such as steel coated with a protective layer of plastic which may be of the same type as that of which the liner 12 is made and may be intimately bonded to the plastic by an extrusion process toprovide a wire with a uniform wall thickness. The surface of the wire may be acid etched in order to facilitate the adequate bonding of the plastic to the wire as it passes through the extrusion die. This provides a wire having high resist ance to destruction or displacement by abrasive or other forces. The novel means of the present invention are employed for placing the wire 16 about the liner 12 in a tightly wound heiix pattern.

The method utilized and one form of mechanism suitable for this purpose are shown in FIGS. 1 and 2. In these figures it will be noted that a coil winding machine 56 having a bed frame 57 is provided. This machine is similar in structure to a lathe and is provided with a power driven rotating chuck 58 having a central open hub (not shown) so that the liner 12 delivered from a supply reel 59 may be passed through the hub and through the chuck 58. A coil winding attachment 61 is positioned in the chuck so that the liner 12 passes through central opening 61] and toward a hollow spindle tail stock 62. The coil winding attachment 61 provides rotating support for a wire supply reel assembly 63, a tensioning mechanism 64, and a preforming roller 66 (shown in FIG. 2).

In the use of this apparatus, a spool of the previously coated reinforcing wire 16 is placed on the wire supply reel assembly 63, and the wire is threaded between the bed rolls 67 and the adjustable roll 63 of the tensioning mechanism 64. Thereafter the Wire 16 is wound tightly about the preforming roller 66, and from there it is wound about the liner 12. The tension exerted by the tensioning mechanism 64- is adjusted by movement of the adjusting screw 69 until the wire 16 coming oh" the supply reel assembly 63 is deformed sufliciently to take out any initial stresses in the wire.

In addition to this means of adjusting the tensioning of the wire 16, it is possible to further adjust the force tending to tightly wind the wire 16 about the liner 12 by adjusting the force exerted against the brake shoe 71. In the embodiment shown, a second adjusting screw 72 is used to hold and keep the brake shoe 71 in intimate contact with the brake drum 73 of the supply reel assembly 63.

After proper adjustment of the elements named, the chuck 68 and coil winding attachment 61 are rotated about the liner 12 in the direction indicated by the arrow as shown in FIG. 2. This rotating movement of the winding attachment 61 results in the placement of a tightly wound coil of the reinforcing wire 16 about the liner 12. When the rotational speed of the winding attachment 61 is adjusted in accordance with the speed of the motor 74 which drives the take-up reel '76, the desired protective placement of the reinforcing wire 16 about the liner 12 will be obtained. The use of a preforming roller 66 of smaller diameter than the exterior diameter of the liner 12 is of special importance where high tensile strength steel wires are being used. Passage over and around the preforming roller 66 prestresses the wire so that it will move into intimate engagement with the liner 12 due to the residual bending of the wire 16.

While the present embodiment illustrates the application of only the tightly wound helix reinforcing wire 16, it is obvious that further mechanism can be provided for the placing of longitudinal tensioning wires and the loosely coiled shield wire for holding them in place, such further mechanism being arranged to apply these additional wires prior to placement of the reinforced tubing on the take-up reel 7 6.

The apparatus illustrated and the method of this invention make it possible to produce continuous lengths of reinforced tubing or the like.

While the specific embodiment of the invention and method have been illustrated and described, various other applications and modifications will occur to those skilled in the art. Therefore, it is not intended that the invention be limited to the details illustrated and described and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.

I claim:

1. The method of forming a helical coil of spring wire or the like about a cylindrical form in intimate engagement therewith which comprises providing a cylindrical form of the desired length, moving the wire along a path substantially tangential to the form and trans: versely thereof in a plane substantially normal to the axis of the form while producing relative rotation of the path and the form continuously at a uniform rate about said axis, guiding the moving wire and bending it in said plane at a position spaced from the point of contact of the wire and the surface of the form to deform the wire in a curve having a radius of curvature less than that of the form and having its center of curvature on the side of the wire toward the form, maintaining the stress in the wire substantially uniform, and concurrently moving the form and the tangential path of the wire axially relatively to one another whereby a helical coil is produced continuously about the form in intimate engagement therewith.

2. The method of forming a helical coil of spring wire or the like about a cylindrical form in intimate engagement therewith which comprises providing a cylindrical form of the desired length, providing a supply of wire rotatable with respect to the form, moving the wire from the supply into a path adjacent and substantially tangential to the form and transversely thereof in a plane normal to the axis of the form, holding the form against rotation about the axis thereof while concurrently rotating the supply and the tangential path of the wire about the form to move the path continuously around the form at a uniform rate about said axis, bending the wire at a position located a selected radial distance from the form to deform the wire in an are having a radius of curvature less than that of the form and lying in said plane with its center of curvature on the side of the wire toward said axis whereby the wire is continuously deformed before being wrapped about the form, maintaining the stress in the wire substantially uniform, and concurrently moving the form axially away from said plane whereby a helical coil is produced continuously about the form in intimate engagement therewith.

3. An apparatus for continuously wrapping helically coiled spring wire and the like about cylindrical forms comprising a first unit for holding a cylindrical form to be wrapped with wire, a second unit for forming wire to be wrapped on the form, means mounting said units for relative rotation with respect to one another about the axis of a form held on said first unit means for driving one of said units for producing relative rotation of said units about said axis, means on said second unit for directing the wire along a path normal to said axis and sub stantially tangential to the form mounted in said first unit, means on said second unit for bending the wire in said path in a plane normal to the axis of the form and with a radius of curvature less than that of the form about a center on the side of the wire toward said axis, means for controlling the stress in the wire and for maintaining uniform the rate of relative rotation of said units, and means for moving the form along its axis whereby a helical coil is produced continuously about the form in intimate engagement therewith.

4. Apparatus for producing a reinforced tubing structure comprising a frame, a power driven rotary member having a central feed opening therethrough, means for introducing a tubing member through said opening, means for holding the tubing member stationary in said opening, a reinforcing wire supply mounted on said rotary member for rotation about the axis of said opening, means for threading the reinforcing wire from said supply through a path including a portion adjacent said opening substantially tangential to the tubing member intro duced therethrough whereby the wire is rotated about the tubing in said opening and thereby wrapped about the tubing, a wire preforming element mounted on said member adjacent said path for bending the Wire in a curve lying in a plane normal to said axis and having a radius of curvature less than that of the tubing member about a center on the side of the wire toward said axis whereby said wire is preformed to said curvature before being wrapped about said tubing, and means for progressively moving said tubing axially through said central opening whereby the separate turns of the wrapping are uniformly arranged on said tube in intimate engagement therewith.

5. Machine means for producing a reinforced tubing structure comprising a frame, a power driven rotary member having a central feed opening therethrough, means for introducing a tubing member through said opening, a reinforcing wire supply real rotatably mounted on said rotary member for planetary movement with respect thereto and about the tubing member introduced through said central opening, a preforming roll member of diameter smaller than the exterior diameter of said tubing, means for threading said reinforcing wire delivered from said supply reel about said preforming roll for initially forming convolutions in said wire of diameter smaller than the diameter of said tubing and thereafter introducing said reinforcing wire along a path substantially normal to the axis of said tubing and into helix pattern about said tubing, and means for progressively moving said tubing outwardly through said central opening so that the separate convolutions of said helix pattern are arranged in regulated tubing reinforcing pattern.

6. Machine means for producing a reinforced tubing structure comprising a frame, a power driven rotary member having a central feed opening therethrough, means for introducing a tubing member through said opening, a reinforcing wire supply reel rotatably mounted on said rotary member for planetary movement with respect thereto and about the tubing member introduced through said central opening, a wire tensioning mechanism likewise mounted on said rotary member, a preforming roll member of diameter smaller than the exterior diameter of said tubing, means for threading said reinforcing wire delivered from said supply reel through said wire tensioning mechanism about said preforming roll for initially forming convolutions in said wire of diameter smaller than the diameter of said tubing and thereafter introducing said reinforcing wire along a path substantially normal to the axis of said tubing and into helix pattern about 5 6 said tubing, and means for progressively moving said tub- 2,513,106 6/ 1950 Prendergast 128133 X ing outwardly through said central opening so that the 2,743,759 5/1956 Snow et al. 156-143 separate convolutions of said helix pattern are arranged 3,028,291 4/1962 Roberts et al. 156143 in regulated, tubing reinforcing pattern. 3,037,343 6/ 1962 Haas et a1. 57-9 5 FOREIGN PATENTS References Cited by the Examiner UNITED STATES PATENTS 835,174 9/1938 France.

1,137,943 5/ 1915 Aine 242-11 FRANK J. COHEN, Primary Examiner.

gj gfzgg al EARL M. BERGERT, MERVIN STEIN, Examiners.

2,313,618 3/ 1943 Bridges 24211 P. DIER, D. E. WATKINS, Assistant Examiners, 

1. THE METHOD OF FORMING A HELICAL COIL OF SPRING WIRE OR THE LIKE ABOUT A CYLINDRICAL FORM IN INTIMATE ENGAGEMENT THEREWITH WHICH COMPRISES PROVIDING A CYLINDRICAL FORM OF THE DESIRED LENGTH, MOVING THE WIRE ALONG A PATH SUBSTANTIALLY TANGENTIAL TO THE FORM AND TRANSVERSELY THEREOF IN A PLANE SUBSTANTIALLY NORMAL TO THE AXIS OF THE FORM WHILE PRODUCING RELATIVE ROTATION OF THE PATH AND THE FORM CONTINUOUSLY AT A UNIFORM RATE ABOUT SAID AXIS, GUIDING THE MOVING WIRE AND BENDING IT IN SAID PLANE AT A POSITION SPACED FROM THE POINT OF CONTACT OF THE WIRE AND THE SURFACE OF THE FORM TO DEFORM THE WIRE IN A CURVE HAVING A RADIUS OF CURVATURE LESS THAN THAT OF THE FORM AND HAVING ITS CENTER OF CURVATURE ON THE SIDE OF THE WIRE TOWARD THE FORM, MAINTAINING THE STRESS IN 